i'm gonna disagree with crasher a little here. the pipe leans out the top quite a bit IMO. you could just buy a handful of mains but good luck getting the needle right. the needle controls 1/4 to 3/4 throttle where most riding is done. get the dj kit.
Two things about the DJ kit. You'll gain power because the needle taper is better on the DJ needle. Secondly, when I put the SW pipe on my H1 they (Speedwerx) told me that the large pilot that was supplied could be reduced down if I was using a DJ needle (which I was). I went from a 48 (I believe that's what they sent with the pipe) and now I run a 42...and it's spot on.
That just shows how bad the stock needle is after you install a pipe or a snorkel because they have to raise the pilot size to help the jeting curcit because the needle does not supply the needed fuel.
that needle is worth the money as far as making the bike run right
I would stick the needle on the 4th knotch. along with the pilot they sent you (with your pipe) and maybe a 142 main jet and se how that does. If you had a 2" snorkel i would say the 146-150dj mian would be best but without iam going to guess a good place to start would be the 142.
I run a DJ 144 main with a #42 pilot three turns out. Runs decent but I think it needs a #45. I don't get backfire, but still get a little grumbling (best I can describe it) on deceleration. I have a drilled out stock exhaust and 2" snorkel.
ok, so i read the instructions and added a 146dj and put the needle on the 3rd clip, it runs great! it seems to be a little sluggish on the top, what should my next move be? on a good note it does not backfire anymore